Energy-delivery system and method for controlling blood loss from wounds

ABSTRACT

An energy delivery system for controlling blood loss is provided. The system includes an energy-activated patch configured for placement on tissue. The patch includes an energy-delivering layer configured to deliver energy to the tissue. The system also includes an energy source in operative engagement with the energy-activated patch for energizing the energy-delivering layer.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No. 13/477,360, by W. O. Reid, Jr., et al., filed on May 12, 2012 and published as U.S. Patent Application Publication US 2013/0317407 A1 on Nov. 28, 2013, the entire contents of which is incorporated by reference herein.

BACKGROUND

1. Technical Field

The present disclosure relates to controlling blood loss, and, in particular, to an energy delivery system and method for the sealing and/or coagulation of a wound for controlling and stopping blood loss.

2. Description of Related Art

In situations involving traumatic wounds, controlling bleeding within the first hour or “golden hour” leads to improved survival rates. Typical methods for control of blood loss include tourniquets and compression bandages. Additionally, in recent years, the military has introduced the use of coagulants, such as zeolite, that promote clotting of wounds.

Tourniquets and other devices may cause collateral damage to surrounding tissue and fail to actively coagulate the wound. Further, tourniquets are not always feasible for particular types of wounds, such as chest wounds. A system that can effectively stop the loss of blood from injuries caused by accidents, warfare and natural disasters would be a vital tool in the stabilization and triage of patients.

SUMMARY

The present disclosure relates to blood loss control, and, in particular, to energy delivery systems and methods for the sealing and/or coagulation of a wound.

According to an aspect of the present disclosure, an energy delivery system for controlling blood loss is provided. The system includes an energy-activated patch configured for placement on tissue. The patch includes an energy-delivering layer configured to deliver energy to the tissue. The system further includes an energy source in operative engagement with the energy-activated patch for energizing the energy-delivering layer. The patch further includes an energy-activated gel layer in proximity to the energy-delivering layer. The energy-activated gel layer includes a coagulant. The energy-activated gel layer includes a medicament.

The energy-activated patch further includes a tissue support layer in proximity to the energy-activated gel layer. The tissue support layer includes a bio-material.

The energy-activated patch further includes a barrier layer in proximity to the energy-delivering layer. The barrier layer is disposed between the energy-activated gel layer and the energy-delivering layer. The barrier layer includes an occlusive dressing.

The energy-delivering layer includes a microstrip antenna or electrodes. The energy-delivery layer can include a microwave mesh patch or a grid of active and return RF electrodes. The energy source is portable and can be a microwave generator or a RF generator. The energy delivery system further includes a thermocouple sensor operatively engaged to the patch.

In another aspect of the present disclosure, an energy-activated patch configured for placement on tissue includes an energy-activated gel layer; and an energy-delivering layer in proximity to the gel layer. The gel layer includes a heat-activated coagulant. The patch further includes a tissue support layer in proximity to the gel layer. The tissue support layer includes a bio-material.

In a further aspect of the present disclosure, there is provided a method for controlling blood loss. The method includes the steps of applying an energy-activated patch and an energy activated gel to a wound site, and supplying energy to the energy-activated patch to create a seal at the wound site by the energy activated gel. The method also includes the step of applying an occlusive dressing to the wound site after applying the gel to the wound site. The method also includes applying an occlusive dressing to the wound site prior to applying the energy-activated patch to the wound site.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other advantage will become more apparent from the following detailed description of the various embodiments of the present disclosure with reference to the drawings wherein:

FIG. 1 is a schematic diagram of an exemplary system for supplying energy to an energy-activated patch for delivery to a wound site in accordance with a first embodiment of the present disclosure;

FIG. 2 is a cross-sectional view of an energy-activated patch in accordance with a second embodiment of the present disclosure;

FIG. 3 is a cross-sectional view of an energy-activated patch having a microstrip antenna embedded within gel in accordance with a third embodiment of the present disclosure;

FIG. 4. is an exploded view of an energy-activated patch with a microwave mesh patch in accordance with a fourth embodiment of the present disclosure;

FIG. 5 is an exploded view of a patch having an energy-delivering layer which includes a grid of RF active and return electrodes in accordance with a fifth embodiment of the present disclosure;

FIG. 6 is a cross-sectional view of a patch having an energy-delivering layer which includes a microwave mesh patch in accordance with a sixth embodiment of the present disclosure; and

FIG. 7 is a flow chart illustrating a method for controlling blood loss from wounds using an energy-activated patch in accordance with the present disclosure.

DETAILED DESCRIPTION

Embodiments of the presently disclosed system and method for controlling blood loss will now be described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. Even though features may be described herein with respect to a particular embodiment, it is understood that the various features described herein can be incorporated within other embodiments.

In one embodiment, an energy delivery system for controlling blood loss is provided. The system includes an energy-activated patch configured for placement on tissue. The patch includes an energy-delivering layer configured to deliver energy to the tissue. The system further includes an energy source in operative engagement with the energy-activated patch for energizing the energy-delivering layer. The patch further includes an energy-activated gel layer in proximity to the energy-delivering layer. The energy-activated gel layer includes a coagulant. The energy-activated gel layer includes a medicament.

The energy-activated patch further includes a tissue support layer in proximity to the energy-activated gel layer. The tissue support layer includes a bio-material. The energy-activated patch further includes a barrier layer in proximity to the energy-delivering layer. The barrier layer is disposed between the energy-activated gel layer and the energy-delivering layer. The barrier layer includes an occlusive dressing.

The energy-delivering layer includes a microstrip antenna or electrodes. The energy-delivering layer can include a microwave mesh patch or a grid of active and return RF electrodes. The energy source is portable and can be a microwave generator or an RF generator. The energy delivery system further includes a thermocouple sensor operatively engaged to the patch.

In another embodiment, an energy-activated patch configured for placement on tissue includes an energy-activated gel layer; and an energy-delivering layer in proximity to the gel layer. The gel layer includes a heat-activated coagulant. The patch further includes a tissue support layer in proximity to the gel layer. The tissue support layer includes a bio-material.

In a further embodiment, there is provided a method for controlling blood loss. The method includes the steps of applying an energy-activated patch and an energy activated gel to a wound site, and supplying energy to the energy-activated patch to create a seal at the wound site by the energy activated gel. The method also includes the step of applying an occlusive dressing to the wound site after applying the gel to the wound site. The method also includes applying an occlusive dressing to the wound site prior to applying the energy-activated patch to the wound site.

Reference is first made to FIG. 1, which shows an energy delivery system 100 in contact with the surface of a patient's skin 20, the energy delivery system 100 includes a terminal 30 connected to an energy source 40, such as an RF or microwave generator, via a wire or cable 50 and a patch 60. The patch 60 has an energy-delivering layer 65 for delivering energy to the wound 70 when the energy source 40 is activated. The energy promotes active coagulation of the blood thus sealing the wound 70 and stopping blood loss. One or more thermocouple sensors 80 incorporated into the patch 60 monitor the skin 20 and/or the temperature of the patch 60 for safety and treatment monitoring.

The energy-delivering layer 65 may include coagulants and/or hemostatic materials which are activated by heat. Therefore, as the energy delivered to the energy-delivering layer 65 heats the layer 65, the coagulants and/or hemostatic materials which are included with the layer 65 are activated. The activated coagulants and/or hemostatic materials exhibit coagulation and/or hemostatic properties which stop or minimize blood loss at the wound 70.

The energy source 40 may be a small handheld device suitable for use, for example, by military medics. In an alternative embodiment, the energy source 40 may be portable and configured for connecting to an electrical outlet of a vehicle, such as an ambulance. In particular, the energy source can by any type of energy source capable of delivering energy of sufficient amount for activating the coagulants and/or hemostatic materials within the energy-delivering layer 65. For example, the energy source can be of the type capable of delivering microwave, RF, or other forms of energy.

The energy-delivering layer 65 does not necessarily need to include any coagulants and/or hemostatic materials. For example, the energy-delivering layer can be manufactured from materials capable of delivering energy in the form of heat to the wound 70 for stopping blood loss by cauterization or charring of the tissue. In such an embodiment, the thermocouple 80 can be used to monitor the temperature of the energy-delivering layer 65 to prevent excessive burning of the tissue.

In accordance with another embodiment with reference to FIG. 2, an energy delivery system 200 includes an energy-activated patch 150 having a gel 110 and an energy-delivering layer 120. The gel 110 is used to facilitate adhesion of the energy-delivering layer 120 to the skin 190. A terminal 160 is provided on the patch 150 for connecting to an energy source (not shown) via a wire or cable 170.

The tissue-contacting surface 140 of the gel 110 may also have coagulants and/or hemostatic materials that promote coagulation of the blood. The coagulants and/or hemostatic materials may promote coagulation upon making contact with blood at the wound site 180 or upon being heated by the energy delivered by the energy source. The gel 110 can serve as a spacer/medium between the tissue or skin 190 to be heated and the energy-delivering layer 120. As a spacer/medium, the gel 110 increases the surface area of tissue 190 exposed to the radiation being delivered by the energy-delivering layer 120.

In embodiments described herein, depending on the gel or other gel-like substance used (collectively referred to herein as gels), the gel can coagulate upon heating or upon making contact with blood. In embodiments described herein, the gel includes one or more drugs therein which are delivered upon activation of the gel or upon application of the patch 150 on the wound 180. The drugs can be, for example, a pain reliever, anesthetic, etc.

Additionally, in embodiments described herein, the gel can be a hydrogel of the type manufactured by Covidien Ludlow. Further, in embodiments described herein, the gel can also be bovine serum albumin powder (BSA) dissolved in water. In other embodiments, the gel may be adhesive, viscous, liquid, solid and/or flexible.

In reference to FIG. 3, there is shown another embodiment of an energy delivery system 300. The system 300 includes a patch 310 having an energy-delivering layer 335 configured to contact the skin 390. The energy-delivering layer 335 can include a microstrip antenna 320. The microstrip antenna 320 is placed on a dielectric substrate 330 which in turn is placed on a ground plane layer 340. The radiation pattern of the microstrip antenna 320 covers a wide area. The microstrip antenna 320 can include a microwave mesh patch. Other antenna structures can be utilized in place or in addition to the microstrip antenna 320.

The energy-delivering layer 335 includes an adhesion material 350, which can include a gel. The adhesion material 350 covers the microstrip antenna 320 and the dielectric substrate 330. The adhesion material 350 can include material which prevents the attenuation of the energy delivered to the tissue, and/or material which increases the amount of surface area of the skin exposed to the microwave radiation. The energy is delivered from an energy source (not shown) coupled via a wire or cable 370 to a terminal 360. The terminal is fixed or connected to the microstrip antenna 320.

In a further embodiment of the present disclosure, energy may be delivered to the patches described herein by various modalities including, but not limited to, RF and microwave. If microwave energy is used, then the microstrip antenna shown by FIG. 3 can be, for example, a microwave mesh patch. The microwave mesh patch can include shielding capable of directing energy generated by the energy source towards the wound site. If RF energy is used then the patch can include or be replaced with material having a grid of active and return RF electrodes that generate heat in the gel. Resistive heating is also contemplated.

With reference to FIGS. 4 and 5, there are shown exploded views of a patch having several layers, including a microwave mesh patch in accordance with a fifth embodiment of the present disclosure and a layer having RF active and return electrodes in accordance with a sixth embodiment of the present disclosure. Both embodiments of the patch include a tissue support layer 20, 21 adjacent to, or embedded within, a gel layer 24, 25 to provide structural support to the wound area. The support layer 20, 21 may be a scaffold made of a bio-material, such that the support layer 20, 21 is absorbed by the tissue over time.

In embodiments, the support layer 20, 21 and/or the gel layer 24, 25 include medicaments, coagulants, etc. The patch shown by FIG. 4 includes an energy-delivering layer 22 which includes a grid of RF active and return electrodes. The patch shown by FIG. 5 includes an energy-delivering layer 23 having a microwave mesh patch. A backing 26, 27 can be provided, which lies adjacent to the energy-delivering layers, 22, 23.

A terminal (not shown) is provided to each patch for delivering energy from an energy source to the energy-delivering layers 22, 23. The terminal can be connected directly to the layers 22, 23. As described herein with respect to the other embodiments, energy is delivered to the patches shown by FIGS. 4 and 5 by the energy source after the patch has been placed over a wound site.

The energy activates the gel layer 24, 25 for causing the gel layer 24, 25 to promote coagulation as described herein for the other embodiments. For example, coagulants and/or hemostatic materials within the gel layer 24, 25 promote coagulation upon being heated by the energy delivered by the energy source. The coagulants and/or hemostatic materials may also be selected for promoting coagulation without being heated.

In reference to FIG. 6 there is shown another embodiment of an energy delivery system 600 according to the present disclosure. The system 600 includes a patch 610 having a barrier layer 620 disposed between an energy-delivering layer 630 and a gel layer 640 to prevent the gel 640 from sticking to the energy-delivering layer 630. The barrier layer 620 may be made of any material that prevents the energy-delivering layer 630 from making direct contact with the gel layer 630. The material can be an occlusive dressing. The material may also be selected to have a low radiation deflection property to prevent the deflection of the energy delivered to the gel layer 630 through the barrier layer 620. A material known to have a low deflection property that may be used for the barrier layer 620 is Tykek® spunbonded olefin. In embodiments, the barrier layer 620 and the gel 640 may be an occlusive dressing, such as HyFin® chest seal.

In embodiments described herein, the thickness of the various components and layers shown by the Figures are for illustrative purposes only and do not necessarily indicate desired proportions of these components and layers.

FIG. 7 illustrates a flow chart showing a method according to the present disclosure. The method includes applying gel to a wound site, step 32. The gel can be applied with an energy-activated patch, as the patches described herein, or prior to placing the patches described herein on the wound site. It is also contemplated that the gel is applied prior to applying the patch and that the patch also include a gel layer. A barrier layer can be placed over the gel applied to the wound site.

After the gel is applied in step 32, the energy-activated patch is applied to the wound site, step 33. Energy is then supplied to the wound site via the energy-activated patch, step 34. Once the patch is activated it promotes coagulation for controlling blood loss and sealing the wound, step 35.

In embodiments, the energy is delivered directly to the wound site using an energy-delivery system as shown, for example, by FIG. 1, or by FIGS. 3-6 with the gel layer removed.

The energy delivery systems described herein can be applied in military applications. For example, energy-activated patches could be issued to military personnel prior to deployment into a battle situation. A portable, handheld energy source can be used to energize the patches if necessary on the battlefield. The energy source can also be issue to military personnel or to military medics.

The energy delivery systems can also be used in non-military applications, such as, for example, paramedics or hospitals. The systems can be provided to ambulance companies for usage in emergency situations where controlling bleeding is paramount.

Features of the various embodiments of the energy-delivery systems and patches described herein in accordance with the present disclosure may be incorporated into one or more other embodiments. Further, embodiments can be designed for different functional frequencies. Additionally, various sizes and shapes can be designed for different treatment modalities and types of wounds. Possible shapes can be rectangular, circular, square, triangular and amorphous. Flexible materials can also be used for the various components described herein to allow for adequate contact and shaping of the patch. The various components can also be made of bio-materials which may be absorbed within the wound site after a time period.

Although the illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various other changes and modifications may be affected therein by one having ordinary skill in the art without departing from the scope or spirit of the invention. Accordingly, various modifications and variations can be made without departing from the spirit or scope of the invention as set forth in the following claims both literally and in equivalents recognized in law. 

1. (canceled)
 2. An energy delivery system for delivering energy to a wound and controlling blood loss by promoting coagulation of the blood thus sealing the wound, the system comprising: an energy-activated patch configured for placement on tissue in proximity to the wound, the patch includes an energy-delivering layer configured to deliver energy to the wound to promote coagulation of the blood thus sealing the wound, the energy-delivering layer including a grid of active and return RF electrodes; and an energy source in operative engagement with the energy-activated patch, the energy source configured to energize the grid of active and return RF electrodes to activate the energy-activated patch.
 3. The energy delivery system according to claim 2, wherein the patch further includes an energy-activated gel layer in proximity to the energy-delivering layer.
 4. The energy delivery system according to claim 3, where the energy-activated gel layer includes a coagulant.
 5. The energy delivery system according to claim 3, wherein the energy-activated gel layer includes a medicament.
 6. The energy delivery system according to claim 4, wherein the energy-activated patch further includes a tissue support layer in proximity to the energy-activated gel layer.
 7. The energy delivery system according to claim 6, wherein the tissue support layer includes a bio-material.
 8. The energy delivery system according to claim 2, wherein the energy-activated patch further includes a barrier layer in proximity to the energy-delivering layer.
 9. The energy delivery system according to claim 4, wherein the energy-activated patch further includes a barrier layer disposed between the energy-activated gel layer and the energy-delivering layer.
 10. The energy delivery system according to claim 9, wherein the barrier layer includes an occlusive dressing.
 11. The energy delivery system according to claim 2, wherein the microstrip antenna includes a microwave mesh patch.
 12. The energy delivery system according to claim 2, wherein the energy source is portable.
 13. The energy delivery system according to claim 2, wherein the energy source is at least one of a microwave generator and an RF generator.
 14. The energy delivery system according to claim 2, further including a thermocouple sensor operatively engaged to the patch.
 15. An energy delivery system for delivering energy to a wound and controlling blood loss by promoting coagulation of the blood thus sealing the wound, the system comprising: an energy-activated patch configured for placement on tissue in proximity to the wound, the patch includes an energy-delivering layer configured to deliver energy to the wound to promote coagulation of the blood thus sealing the wound, the energy-delivering layer including a microstrip antenna; and an energy source in operative engagement with the energy-activated patch, the energy source configured to energize the microstip antenna to activate the energy-activated patch.
 16. The energy delivery system according to claim 15, further comprising a dielectric substrate at least partially disposed on a surface of the microstrip antenna.
 17. The energy delivery system according to claim 16, wherein the dielectric substrate is at least partially disposed on a surface of the energy-delivering layer.
 18. The energy delivery system according to claim 17, further comprising a ground plane layer at least partially disposed on a surface of the dielectric substrate.
 19. The energy delivery system according to claim 15, wherein the energy-activated patch further includes an energy-activated gel layer in proximity to the energy-delivering layer.
 20. The energy delivery system according to claim 19, wherein the energy-activated patch further includes a tissue support layer in proximity to the energy-activated gel layer.
 21. The energy delivery system according to claim 15, wherein the energy-activated patch further includes a barrier layer in proximity to the energy-delivering layer. 